Asthma morbidity and mortality in poor, urban populations is unacceptably high. We and others have proposed that allergic sensitization to cockroaches may contribute to this problem. New analysis of our previously completed study of asthmatic adolescents shows even stronger association between indices of asthma severity and cockroach allergy. However, further in-depth assessment is required for the development of environmental policies and urban housing planning that address cockroach infestation in the context of respiratory health. The current grant was designed to provide additional evidence supporting the causal relationship between asthma morbidity and cockroach allergy/exposure. In the first period of this project, the data we have generated through a complete survey of the Claremont public housing complex in Baltimore City indicate that the prevalence of asthma in this population is much higher than the national average. In addition, we find that 60% of asthmatics in this population are sensitized to cockroaches. We continue our strong collaboration with the Housing Authority of Baltimore City and we are in the process of beginning our work in the O'Donnell Heights complex. This development is scheduled for demolition by the end of 2005, with new units available in 2007. We request renewal of this grant with the following aims. In Aim 1, we will survey the entire O'Donnell population so that we have full asthma prevalence data of a representative sample of public housing residents. Survey results will be validated with determination of airways responsiveness. Within the O'Donnell population, we will perform a cross-sectional study in individuals with asthma evaluating risk factors for asthma morbidity with focus on cockroach and other allergen exposure, endotoxin exposure, exposure to indoor air pollutants (PM2.5 and PM10) and obesity. To ascertain the relationship between the above risk factors and the presence of asthma, we will perform a case-control study involving the O'Donnell residents with asthma vs. a group of residents with lone rhinitis and a healthy group. In Aim 2, we will monitor asthma morbidity longitudinally in all asthmatic residents of O'Donnell Heights, while they are relocated into new homes. It is our hypothesis that those with cockroach allergy who will be relocated to cockroach-free environment will experience improvement in airway disease. Aim 3, consists of a randomized, parallel study utilizing individuals relocating into the new units that are replacing the Claremont complex. This study will test the effectiveness of an education/behavioral modification program, combined with precision-targeted early mitigation, against no intervention, in avoiding cockroach infestation of new homes. We hope that with the data to be generated, we will positively impact the health of urban US populations who are disproportionally suffering from asthma morbidity and mortality.